In recent years, the wish to increase the rate of fire also for heavy artillery pieces has grown ever stronger. Consequently, several different designs have been proposed in the art. Many of these are based on the employment of fixed magazines which may be of the revolver type or of other design and from which projectiles and propellant charges, either separately, as a unit, or jointly but without physical connection, are transferred to and rammed home in the gun. With fixed magazines and guns which can be moved both in elevation and in traverse and which thus move in relation to the magazine, at least two angular planes and often also one vertical plane must, as a rule, be overbridged before the shell and its propellant charge can be rammed home. In fully automatic loading, this problem is generally solved with the aid of a plurality of ammunition handling cradles which are each pivotal in their plane. By transferring shells and propellant charges between these cradles, all angular and level differences between the breech of the gun and the angular position of the gun barrel and the magazine can be negotiated. However, such designs are of a highly complex nature and it is doubtful whether their complexity is worth the advantages which are attained in that the relatively heavy magazines can be rendered stationary. In addition, the transfer operations of shell and propellant charge between several raisable and pivotal handling cradles is substantially time consuming so, with the result that it is very difficult, employing these designs, to achieve the extremely short ramming times which are current objectives within the art. One main reason for this is that, in combatting a specific target, the ideal situation is to have several shells launched on their way towards the target already before the first shell strikes home.
Patent specification EP AO 051 119 discloses a loading system for large-caliber artillery pieces in which the shell and propellant charge magazines which are here of revolver type are carriage-fixed but not elevatable with the gun, that is they follow the barrel on its angular alignment but not its elevation. In this design, use is made of separate, moving charge cradles or bridges for transferring shells and propellant charges from each respective revolver magazine to the loading position of the gun immediately outside its breech opening and are there aligned in the main axis of the gun barrel. In turn, the loading cradles are each journalled in its pivotal aim disposed beside the gun barrel, this arm being in turn pivotally journalled about that shaft about which the gun barrel is elevated. Thus, the pivotal arms are each movable in a plane lying parallel with the gun barrel. The axes of rotation of the loading cradle are in their turn disposed in the longitudinal direction of the pivot arms. Thus, in this design a two-step or double-action displacement is required of each respective loading cradle from having received a projectile or propellant charge. First, each respective pivot arm must be swung into a position which corresponds to the breech opening of the gun barrel and each respective shell or propellant charge is rammed home.